POLYHEDRAL MODELING WITH MULTIPRECISION INTEGER ARITHMETIC

We describe a polyhedral modeller that uses software extended-precisio n integer arithmetic to guarantee numerical reliability. By careful de sign, the performance of the modeller is not much different from the p erformance that a floating-point modeller might have. The modeller per forms Boolean set operations exactly; to prevent growth of coordinate bit-length, affine transformations require coordinate rounding and hen ce are approximate. A new algorithm for reconstructing polyhedral inci dence information after rounding is given. Copyright (C) 1996 Elsevier Science Ltd